70% of Playdom’s revenue comes from direct payments, the company says, 10% is advertising and 20% is offers. For offers, they work with usual suspects. But they have banned the spammier stuff, like mobile subscriptions.

One thing’s for sure. Zynga has more users of its games than Playfish and Playdom combined, and they tend to monetize far better, too (at least until last weekend). It’s not unreasonable to imply a $1 billion valuation to Zynga based on these comps. They’ll be looking to the public markets, though, for their exit.